Ruthenium complexes as catalysts for reduction of polyenes

ABSTRACT

Complexes of zero-valent ruthenium and ligands suitable for the selective reduction of polyenes to monoenes are disclosed.

United States Patent Fahey Dec. 9, 1975 RUTHENIUM COMPLEXES AS CATALYSTS[56] References Cited FOR REDUCTION OF POLYENES UNITED STATES PATENTSInventor: yl R- y, Bartlesville. Okla- 3,113,986 12/1963 Breslow 6161.260/6839 3.387.932 6/1968 PinO Clal 23/203 [73] Assgnce' g if gii ampany3,488,400 1/1970 Candlin et al. .1 260/677 H a 3,597,461 8/]971L'Eplattenier 6161 260/429 22 u D 20 1972 3,607.050 9/l971 Chabardes23/203 C [21] Appl' NO: 6317 Primary ExuminerPau| M. Coughlzm. Jr. [44]Published under the Trial Voluntary Protest Assistant EmminerVer0niCa Kf Program on January 28, I975 as document no. B 57 ABSTRACT Related [15-Application Data Complexes of zero-valent ruthenium and ligands suit-[62} Division of Ser. No. M0564, May 5, 1971, able for the selectivereduction of polyenes to monoabandoned. enes are disclosed.

[52] U.S. Cl 260/666 A; 260/677 H 511 lm. c1. C07C 13/00 [58] Field 6:Search 260/666 A, 677 H, 683.9; 4 Claims, N9 Drawings RUTHENIUMCOMPLEXES AS CATALYSTS FOR REDUCTION OF POLYENES 2 Amer. Chem. Soc. 87,4008 (1965). [Ru(CO) is commercially available from Strem Chemicals,lnc., Danvers, Mass. In the above formula, Ph is used to denote phenyl,Ph P being triphenylphosphine.

This is a division of my application Ser. No. 140,564 5 The reductionreaction can be conducted in reaction filed May 5, 1971 now abandoned.media comprising organic solvents which dissolve the This inventionpertains to the reduction of polyenes. reactants and the catalyst butwhich are substantially In one of its more specific aspects, thisinvention inert under the conditions at which the reaction isconpertains to the use of ruthenium complexes as catalysts ducted.Suitable solvents include benzene, toluene, for reduction of polyenes.cumene, isoctane, esters, ethers, ketones and alcohols. The use ofruthenium for the preparation of cyclic If preferred, the reaction canbe conducted without alkenes, the ruthenium being in elemental form, isemploying an added solvent. discussed in US. Pat. No. 3,391,206 toHartog. Such While the invention will be hereinafter illustrated inreduction is nonselective in respect to reducing polyterms of theselective reduction of 1,5,9-cyclododecacues to monoenes. There has nowbeen discovered a triene to cyclododecene, it is to be understood thatthe class of catalysts suitable for the selective reduction of inventionis applicable to cyclic and acyclic polyenes of polyenes to themonoenes. This invention provides up to carbon atoms includingl,3-cyclopentadiene, those catalysts and the method for their use.1,3-pentadiene and l,3,7,9-octadecatetraene.

According to the method of this invention there are In general thereaction is conducted by introducing provided catalysts comprisingruthenium-ligand com- 20 the polyene into a solvent in any desiredconcentration plexes having the general formula Ru,,(CO) (L -,Z),H, andintroducing the ruthenium-ligand complex thereas hereinafter defined.into in an amount within the range of about 0.00001 to Also according tothis invention there is provided a about 0.5 moles of complex per moleof polyene. process for the selective reduction of a polyene in Themixture is maintained at a temperature within which a polyene iscontacted with the aforementioned the range of about 80 to about 180 C.and at a pres complexes under reducing conditions and recovering a surewithin the range of about 1 to about 600 psig by monoene as the product.the introduction of hydrogen, for a period up to about The rutheniumcomplex of this invention comprises 48 hours. The monoene can berecovered from the those complexes comprising zero-valent ruthenium andreaction mixture by conventional techniques. ligands in the form ofsoluble catalyst complexes. By The method of this invention isillustrated by the zero-valent ruthenium" is meant ruthenium which hasreduction of 1,5,9-cyclododecatriene in benzene as the not transferredany of its electrons in chemical bond reaction medium under theconditions indicated. Reformation. sults were as indicated:

Cat. Conc. Run Mole/Mole Temp. Hydrogen Time, No. Catalyst ReactantRange, IC Pressure, psig Min.

1 (Ph PMCOMRu .011 129-159 155-232 70 2 [Ru Co .019 127-145 178-209 1053 [Ru(CO),]= .019 153-161 l66-2l0 70 Product analysis in each of theruns was as follows:

Run Product Composition, Wt. No. Cyclododecane CyclododeceneCyclododecadiene Cyclododecatriene Suitable ligands include those of thegeneral formula L 2 wherein L can be R or R0, wherein R is alkyl, 50cycloalkyl, aryl or combinations thereof including aral- The above dataillustrate the operability of the kyl, alkaryl and the like wherein themaximum number method of this invention to selectively reduce a polyofcarbon atoms is twelve, and Z is one of phosphorous ene to produce amonoene, cyclododecene being oxiand arsenic. dizable tol,l2-dodecanedioic acid, an important pre- Examples of suitable R groupsare methyl, cyclocursor for the formation of polyamides usable asfibers. hexyl, n-dodecyl, benzyl, p-tolyl, 3,5-dimethylphenyl, Forcomparative purposes l,5,9-cyclododecatriene n-hexylphenyl and the likeand their mixtures. was hydrogenated under conditions comparable toOther suitable ligands include carbon monoxide and those of Runs 1through 3, the only significant dissimihydrogen. lar factor being thatruthenium metal deposited on Suitable ruthenium-ligand complexes can beconsidcarbon was employed as the catalyst, the ruthenium ered as havingthe general formula Ru,,(CO),,(L Z),H,, comprising 5 weight percent ofthe catalyst. The prodwherein L and Z are as previously defined, p has auct was analyzed as containing 39.7 weight percent value of from I to 6,q has a value from 3 to l8, r has cyclododecane, 33.0 weight percentcyclododecene, a value of from 0 to 2 and s has a value of from 0 to 4.l2.l weight percent cyclododecadiene and 15.2 weight Suitableruthenium-ligand complexes include percent cyclododecatriene. Thesedata, when coma )2( )s l 4]a )s1 2 a( )1s and the like. (Ph P) (CO Rucan be produced by that method disclosed by J. P. Collman and W. R.Roper, J.

pared with the prior runs, demonstrate that the elemental ruthenium isnonselective when employed for the reduction of polyenes.

It will be evident that various modifications can be made to the methodof this invention. However, such are considered to be within the scopeof the invention.

What is claimed is:

l. A process for the partial hydrogenation of l,5,9- cyclododecatrieneto cyclododecene which comprises contacting l,5,9-cyclododecatriene witha rutheniumligand complex catalyst consisting essentially of (Ph P),(CO)Ru or [Ru(CO),] under hydrogenation conditions which partially reducel,5,9-cyclododecatriene to cyclododecene.

2. The process of claim 1 wherein said rutheniumligand complex is (Ph P)(CO) Ru and said contacting is effected in benzene as the reactionmedium.

3. The process of claim 1 wherein said rutheniumligand complex is[Ru(CO) and said contacting is effected in benzene as the reactionmedium.

4. The process of claim 1 wherein said contacting is effected in thepresence of from about 000001 to about 0.5 moles of ruthenium-ligandcomplex catalyst per mole of l,5,9-cyclododecatriene at a temperaturewithin the range of from about to C, a hydro gen pressure within therange of from about 1 to about 600 psig, and a contact time of up toabout 48 hours. i I"

1. A PROCESS FOR THE PARTIAL HYDROGENATION OF 1,5,9CYCLODODECATRIENE TOCYCLODODECENE WHICH COMPRISES CONTACTING 1,5,9-CYCLODODECATRIENE WITH ARUTHENIUM-LIGAND COMPLEX CATALYST CONSISTING ESSENTIALLY OF(PH3P)2(CO)3RU OR (RU(CO)4)3 UNDER UNDER HYDROGENATION CONDITIONS WHICHPARTIALLY REDUCE 1,5,9-CYCLODODECATRIENE TO CYCLODODECENE.
 2. Theprocess of claim 1 wherein said ruthenium-ligand complex is(Ph3P)2(CO)3Ru and said contacting is effected in benzene as thereaction medium.
 3. The process of claim 1 wherein said ruthenium-ligandcomplex is (Ru(CO)4)3 and said contacting is effected in benzene as thEreaction medium.
 4. The process of claim 1 wherein said contacting iseffected in the presence of from about 0.00001 to about 0.5 moles ofruthenium-ligand complex catalyst per mole of 1,5,9-cyclododecatriene ata temperature within the range of from about 80* to 180*C, a hydrogenpressure within the range of from about 1 to about 600 psig, and acontact time of up to about 48 hours.